The present invention refers in general to a closure for containers, and in particular to a plug for bottles, preferably adapted to be used to plug bottles of wine.
Due to its preferred application as currently provided, the following description will be oriented to the case in which the closure of the invention is applied to the field of bottles for foodstuff, in particular of bottles of wine, so that the closure will assume the configuration of a bottle plug. It is clear, however, that the teachings of the present invention are equally applicable to containers for any type of substance (foodstuff or otherwise) that needs a sealed closure capable on one hand of preventing the contained substance from leaking out, and on the other hand of preventing gases and/or foreign substances (including, for example, the material of which the closure is composed) from entering inside the container.
In the field of plugs for bottles of wine, the most common material of which they are made is cork: such material is costly, increasingly difficult to obtain, since it comes from specific plants and therefore is available in nature in relatively limited amounts.
Moreover, plugs made of cork have many problems from the functionality point of view: studies in the field have demonstrated that in high percentages such plugs damage the wine contained in the bottles, giving it a taste that is no longer the original one and that is always unpleasant to the palate. When the wine contained in these bottles is precious, the presence of a faulty plug is wasteful and implies heavy costs.
Even when plugs made of cork do not show defects, it is advisable to periodically replace them (10-15 years), to avoid spoiling the bottle contents.
Cork also gives rise to problems in terms of its installation and removal from bottles: in fact, automatic plugging machines are exposed to dust and pieces of cork that become detached, polluting the environment and impairing process quality; moreover, cork is a non-uniform material, so that its behaviour differs from one supply batch to the next; finally, when the plug is removed from a bottle, for example using an ordinary corkscrew, it can happen that small bits of cork fall inside the bottle itself and pollute its contents.
Studies are being carried out to produce plugs for bottles made of plastic material that provide equivalent performances to those of plugs made of cork without the abovementioned problems, but the practical results so far are unsatisfactory in various aspects, so that it has not yet been possible to produce a closure that allows the replacement of cork as material (even with all problems generated thereby, as mentioned above), while providing the same positive characteristics.
The object of the present invention is to solve the abovementioned problems of the prior art by providing a closure made of plastic material for containers that has optimum sealing characteristics, preventing gases and/or foreign substances from entering inside the containers and preventing the substance contained in the containers themselves from leaking out.
A further object of the present invention is to provide a closure of the wine bottle plug type that can be applied to the bottle neck sizes that are currently deemed as standard for bottles of this type, that can be adapted without modifications to the automated machinery for plugging bottles themselves and that can be removed from bottles using ordinary removing means of the corkscrew type. Moreover, the plug of the invention allows the organoleptic characteristics of the wine contained to be preserved, and therefore it finds a preferred application in the storage of wines of the still and lightly sparkling types, and in the storage of precious wines.
The above and other objects and advantages of the invention, as will appear from the following description, are obtained by a closure for containers as claimed in claim 1. Preferred embodiments and nonobvious variations of the present invention are claimed in the dependent claims.